Insect and acarid pests destroy growing and harvested crops. In the United States, agronomic crops must compete with thousands of those pests. In particular, tobacco budworms and southern armyworms are especially devastating to crops.
Tobacco budworms cause tremendous economic losses in agronomic crops. In particular, budworms devastate cotton crops by feeding on green bolls. Control of budworms is complicated by their resistance to many common insecticides, including organophosphates, carbamates and pyrethroids.
In spite of the commercial insecticides and acaricides available today, damage to crops, both growing and harvested, caused by insect and acarid pests still occurs. Accordingly, there is ongoing research to create new and more effective insecticidal and acaricidal agents.
Certain pyrimidine compounds are known to possess insecticidal and nematocidal activity (see, e.g., EP 0 506 270). However, none of those compounds are within the scope of the present invention.
It is, therefore, an object of the present invention to provide compounds which are highly effective for the control of insect and acarid pests.
It is also an object of the present invention to provide a method for the control of insect and acarid pests.
It is a further object of this invention to provide a method for the protection of growing and harvested crops from damage caused by insect and acarid attack and infestation.
Those and other objects of the present invention will become more apparent from the detailed description thereof set forth below.
This application is also related to application Ser. No. 09/273,942, filed Mar. 22, 1999, now U.S. Pat. No. 6,153,619.
The present invention describes aryl pyrimidines which are useful as insecticidal and acaricidal agents. Those compounds are also useful for protecting plants from damage caused by insect and acarid attack and infestation.
The aryl pyrimidines used according to the present invention have the structural formula I 
wherein
A and B each independently represent an optionally substituted aryl group;
R1 represents a hydrogen or halogen atom or an optionally substituted alkyl, alkenyl, alkinyl, alkoxy, alkoxyalkyl, alkoxyalkoxy group; or an alkylthio group, alkylsulphinyl or alkylsulphonyl group, an amino, alkylamino or dialkylamino group or a cyano, nitro, haloalkyl, haloalkoxy, haloalkylthio or SF5 group, one of Y and Z represents N and the other represents CR2, in which R2 has the meaning given for R1;
X represents O or NR, in which R represents a hydrogen atom or an alkyl group.
This invention also describes compositions containing those compounds and methods for using those compounds and compositions. Advantageously, it has been found that the pyrimidine compounds of the present invention, and compositions containing them, are useful for the control of insect and acarid pests. The compounds of this invention are also useful for the protection of plants from damage caused by insect and acarid attack and infestation. The pyrimidine compounds are especially useful for the control of tobacco budworms and southern armyworms.
The present invention provides a method for the control of insect or acarid pests which comprises contacting said pests or their food supply, habitat or breeding grounds with a pesticidally effective amount of an aryl pyrimidine of formula I.
The present invention also provides a method for the protection of growing plants from attack or infestation by insect or acarid pests which comprises applying to the foliage of the plants, or to the soil or water in which they are growing, a pesticidally effective amount of an aryl pyrimidine compound of formula I.
The aryl pyrimidines of the present invention have the structural formula I 
wherein A, B, X, Y, Z and R1are as described hereinabove for formula I.
Exemplary of halogen hereinabove are fluorine, chlorine, bromine and iodine.
Preferred formula I aryl pyrimidines of the present invention are those wherein
A and B are each independently phenyl optionally substituted with any combination of from one to three halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy or C1-C4haloalkoxy groups;
R1 and R2 are each independently hydrogen, C1-C4alkyl, C1-C4alkoxy, C1-C4alkylthio, cyano, nitro, amino, C1-C4haloalkyl, C1-C4haloalkoxy or fluorine; and
A is phenyl optionally substituted with any combination of from one to five halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy or C1-C4haloalkoxy groups,
B is phenyl optionally substituted with any combination of from one to three halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy or C1-C4haloalkoxy groups.
More preferred insecticidal and acaricidal agents of the present invention are those wherein
A is phenyl optionally substituted with any combination of from one to three halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy, C1-C4alkylthio or C1-C4haloalkoxy groups;
R1 and R2 each independently are hydrogen, methyl ethyl, fluoro, chloro, cyano, nitro, amino, thiomethyl or trifluoromethyl;
preferably at least one of R1 and R2 is hydrogen; and
A and B are each independently phenyl optionally substituted with any combination of from one to five halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy or C1-C4haloalkoxy groups.
The terms xe2x80x9cC1-C4haloalkylxe2x80x9d and xe2x80x9cC1-C4haloalkoxyxe2x80x9d are defined as a C1-C4alkyl group and a C1-C4alkoxy group substituted with one or more halogen atoms, respectively.
Formula I compounds of this invention which are particularly effective insecticidal agents include the novel compounds of formulae IA and IB: 
R1 and R2 each independently represents a hydrogen or halogen atom or an alkyl, alkenyl, alkinyl, alkoxy, alkoxyalkyl, alkoxyalkoxy group, alkylthio, alkylsulphinyl or alkylsulphonyl group, an amino, alkylamino or dialkylamino group or a cyano, nitro, haloalkyl, haloalkoxy, haloalkylthio or SF5 group, A represents a phenyl group being substituted by one or more of the same or different substituents selected from halogen atoms, alkyl, alkoxy, cyano, nitro, haloalkyl, haloalkoxy, alkylthio, haloalkylthio, alkylsulphinyl, alkylsulphonyl and SF5 groups; and B represents a phenyl group being substituted by one or more of the same or different substituents selected from halogen atoms, alkyl, alkoxy, cyano, nitro, haloalkyl, haloalkoxy, alkylthio, haloalkylthio, alkylsulphinyl, alkylsulphonyl and SF5 groups; 
wherein R1 and R2 have the meaning given in claim 1; A represents a phenyl group being substituted by one or more of the same or different substituents selected from halogen atoms, alkyl, alkoxy, cyano, nitro, haloalkyl, haloalkoxy, alkylthio, haloalkylthio, alkylsulphinyl, alkylsulphonyl and SF5 groups; and B represents a phenyl group being substituted by one or more of the same or different substituents selected from halogen atoms, alkyl, alkoxy, cyano, nitro, haloalkyl, haloalkoxy, alkylthio, haloalkylthio, alkylsulphinyl, alkylsulphonyl and SF5 groups.
Particularly preferred are the compounds of formulae IA1 and IA2
in which R1 and R2 have the meaning given for formulae IA and IB; and
R3 through R8 each independently represent a hydrogen or halogen atom, in particular F or Cl, or a C1-4 alkyl, in particular methyl or ethyl, a C1-4 alkoxy, in particular methoxy or ethoxy, a C1-4 haloalkyl, in particular trifluoromethyl, a C1-4 haloalkoxy, in particular difluoro- or trifluoromethoxy, a cyano or nitro group.
Preferably at least one of the groups R3, R4 and R5 is different from a hydrogen atom and at least one of the groups R6, R7 and R8 is different from a hydrogen atom.
Advantageously, it has been found that the formula I compounds of the present invention are especially useful for the control of tobacco budworms and southern armyworms.
Aryl pyrimidines of the present invention wherein Y is CR1 and Z is N (formula IA) may be prepared by reacting a compound of formula IIA 
in which B, R1 and R2 have the meaning given and L1 is a leaving group, with a compound of general formula IIIA,
Axe2x80x94OM1xe2x80x83xe2x80x83IIIA
wherein
A is defined as for formula IA; and
M1 represents a hydrogen or a metal atom.
Furthermore, the invention relates to a process for the preparation of a compound of general formula IB, which comprises reacting a respective compound of the general formula IIB, 
in which B, R1 and R2 have the meaning given and L1 is a leaving group, with a compound of general formula IIIA,
Axe2x80x94OM1xe2x80x83xe2x80x83IIIA
wherein
A is defined as for formula IB; and
M1 represents a hydrogen or metal atom.
Advantageously, certain formula I compounds of this invention may be derivatized by conventional procedures known in the art to produce other compounds of formula I.
The aryl pyrimidine compounds of the present invention are effective for controlling insect and acarid pests. Those compounds are also effective for protecting growing or harvested crops from damage caused by insect and acarid attack and infestation.
Insects controlled by the aryl pyrimidine compounds of this invention include Lepidoptera such as tobacco budworms, cabbage loopers, cotton boll worms, beet armyworms, southern armyworms and diamondback moths; Homoptera such as aphids, leaf hoppers, plant hoppers and white flies; Thysanoptera such as thrips; Coleoptera such as boll weevils, Colorado potato beetles, southern corn rootworms, western corn rootworms and mustard beetles; and Orthoptera such as locusts, crickets, grasshoppers and cockroaches. Acarina controlled by the compounds of this invention include mites such as two-spotted spider mites, carmine spider mites, banks grass mites, strawberry mites, citrus rust mites and leprosis mites. Advantageously, it has been found that the compounds of the present invention are especially effective against tobacco budworms and southern armyworms.
In practice generally about 10 ppm to about 10,000 ppm and preferably about 100 ppm to about 5,000 ppm of a formula I aryl pyrimidine, dispersed in water or another liquid carrier, is effective when applied to plants or the soil in which the plants are growing to protect the plants from insect and acarid attack and infestation.
The aryl pyrimidine compounds of this invention are also effective for controlling insect and acarid pests when applied to the foliage of plants and/or to the soil or water in which said plants are growing in sufficient amount to provide a rate of about 0.1 kg/ha to 4.0 kg/ha of active ingredient.
While the compounds of this invention are effective for controlling insect and acarid pests when employed alone, they may also be used in combination with other biological chemicals, including other insecticides and acaricides. For example, the formula I compounds of this invention may be used effectively in conjunction or combination with pyrethroids, phosphates, carbamates, cyclodienes, endotoxin of bacillus thuringiensis (Bt), formamidines, phenol tin compounds, chlorinated hydrocarbons, benzoylphenyl ureas, pyrroles and the like.
The compounds of this invention may be formulated as emulsifiable concentrates, flowable concentrates or wettable powders which are diluted with water or other suitable polar solvent, generally in situ, and then applied as a dilute spray. Said compounds may also be formulated in dry compacted granules, granular formulations, dusts, dust concentrates, suspension concentrates, microemulsions and the like all of which lend themselves to seed, soil, water and/or foliage applications to provide the requisite plant protection. Such formulations include the compounds of the invention admixed with agronomically acceptable inert, solid or liquid carriers.